A new study adds to the evidence that kids affect mom’s sleep more than dad’s.

We’ve written about the effect that baby-fatigue can have on the workplace, and now a new study shows that moms are much more likely to suffer from sleep loss than dads.

After analyzing data on sleep habits and self-reported tiredness from more than 5,800 people, researchers from American Academy of Neurology and Georgia Southern University found some startling if unsurprising data points. Only 48 percent of moms under 45 got seven or more hours of sleep per night and for every child a mom had, she was 50 percent “less likely to get six hours of sleep or more per night,” Glamour reported.

Sixty-two percent of women without children reported getting seven or more hours of sleep a night and said that they felt tired about 11 days of the month. Moms reported feeling tired for about two weeks of every month. None of these trends were evident among men.

“Getting enough sleep is a key component of overall health and can impact the heart, mind, and weight,” study author Kelly Sullivan, Ph.D, said in a press release, adding that “I think these findings may bolster those women who say they feel exhausted.”

They’re also good reason for partners to work towards more equitable division of childcare and household chores — two things women tend to do more of than men, Glamour reports, and which may contribute to the unequal effect kids have on parent’s sleep.

Read more on Glamour.

Originally published at medium.com